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NASA blasted for ignoring smaller asteroids

By Jeff Hecht

NASA is being slammed for sacrificing public safety by resisting calls to enlarge its search for potentially dangerous asteroids which might strike the Earth.

“NASA cannot place a new NEO [near-earth object] programme above current scientific and exploration missions,” maintained Scott Pace, associate administrator for program analysis and evaluation at the US space agency. He spoke at a US congressional hearing on Thursday.

NASA has failed to heed a directive Congress passed two years ago to plan and budget for a programme identifying threatening near-Earth objects as small as 140 metres, and to devise ways to avoid potential impacts, he said.

If expanded to the four-telescope array planned in 2010, Pace said “this system alone could discover over 70% of the potentially hazardous objects bigger than 140 metres by 2020”. So far, NASA has contributed less than &dollar;200,000 to Pan-STARRS.

NASA also is talking with developers of the proposed 8.4 metre Large Synoptic Survey Telescope. This would be ideal for asteroid hunting, as it could survey the entire sky every three nights, but building it is set to cost &dollar;300 million. The developers are seeking money from the National Science Foundation.

Essential search

Such a search is a big job because asteroids smaller than 1 km across are faint, and some 20,000 of them are thought to have orbits that could cross Earth’s.

But the hunt for smaller asteroids needs to start, said asteroid researcher Don Yeomans of NASA’s Jet Propulsion Laboratory. “Finding them is the first priority. We can’t mitigate, and we can’t characterise them if we can’t find them,” he told the committee.

The role of the Arecibo radio telescope – earmarked for closure if funds are not renewed – was also stressed by Yeomans and other scientists.

The 305 metre telescope is equipped with one of the world’s two planetary radars. These can give far more precise data on orbits than optical techniques, said Donald Campbell, a Cornell University astronomer who previously ran Arecibo.

NASA has not yet offered to replace the &dollar;10 million operations budget which the National Science Foundation is phasing out for the running of Arecibo, despite agreeing that the telescope is important.

The space agency was also slammed at the hearing as, according to Pace, NASA “has no responsibility for planning deflection” of objects that might threaten the Earth.

With NASA not taking on the task, “no one is in charge of protecting the Earth from impacts”, Schweickart warned the committee. “Until NASA or someone else is given responsibility … that job will not be done.”

Comets and Asteroids – Learn more about the threat to human civilisation in our special report.